Firefly and PC GAMESS-related discussion club

It looks like you starting geometry very close to a transition state. I would recommend you to calculate hessian first and then perturb imaginary mode if it exists. Then try run optimization starting from exact hessian. Algorithms for transition state search and minimum are similar.

Hope this helps.

Pavlo.

On Thu Sep 11 '14 8:48pm, Oleg Levitskiy wrote---------------------------------------------->Dear Pavlo,>optimization with corrected parameters did 9 steps and unfortunately almost all of them with energy encrease. It seems that convergence to the predefined gradient value can't be achieved in case of applying solvent modeling as you've supposed...>Nonetheless I attached the resulting out in hope of appearing of any new ideas.

>>Before apply a solvent correction, you need to optimize the geometry in a gas phase. Make sure you use a right functional. I am skeptical about pbe96. Do not expect very tight gradient for the geometry with the solvent correction. Usually 10^-4 is ok.

>>Pavlo.>>>>>>>>On Tue Sep 9 '14 3:30pm, Oleg Levitskiy wrote>>--------------------------------------------->>>Dear Firefly Users,>>>I've tryed to perform an optimization of anionic complex of Ni (DFT/PBE96, PCM) and faced a problem with convergence. Energy has unexpectedly risen and fluctuate spontaneousely from step to step. I've tryed to increase accuracy (ICUT, ITOL values and also DLCTOL and ORTTOL), to change optimization method (GDIIS, NR), to perform optimization in cartesian or delocalized coordinates, but the result was similar in all cases. Could you advise me something else to solve this problem. >>>The beginning of my input is following: